After a fight Hayate, Nagi heads to the apartment complex to hang out.  But her “little sister” is the only one home.  This might be Nagi’s chance to find out what Ruri’s real goal is. 
Why do old houses make weird noises?
¿Por qué las casas viejas 
hacen sonidos extraños?
¿Por qué las casas viejas siempre hacen ruido?
Por que essas casas antigas 
fazem uns barulhos estranhos?